Sighting devices for archery bows generally are classified in two categories, namely pin sights and crosshair sights. There is considerable variation in the design of pin sights where such designs may include multiple leveling bubbles, built-in range finding windows, quickadjust levers and other options which tend to make such pin sights bulky and difficult to use when hunting game. Cross-hair bow sights generally have a vertical wire and several horizontal cross wires where the vertical wire assists the archer in holding the bow near the vertical and the horizontal cross-hair assists the archer in estimating the distance to the target. There are also pendulum bow sights incorporating aiming pins which operate on the principle that as the archer aims downward at various angles, the aiming pin rotates upward or downward to compensate for the shooting distance to the target. These types of sights are relatively complicated and fragile and the angle range finding principle is not accurate beyond 30 to 35 yards.
Electronic bow sights are also utilized which contain pin beads that electronically light up an appropriate sight pin based upon the distance of the target while also flooding the cross-hair wires with a beam of light. The lighted cross hairs assist the archer in effectively finding a cross hair against the background of various types of shaded terrain.
Without the use of a sighting device, the archer will sight a target by instinct; the hunter draws down on the target, whether a circle on cardboard or an animal, and releases the arrow by feel. The archer must judge the distance and direction to the target by interpretation of the surrounding terrain. When in familiar surroundings, an archer can make judgments which are accurate. However, when the archer is in the woods where there are varying conditions of terrain and elevation, the estimations of distance and elevation are much more difficult to assess while at the same time focusing on an intended target.
Bow sights are variously mounted to the side of the bow handle. Most bow sights bolt rigidly to the side of the bow; however, dovetail mounts are also used which permit the bow hunter to selectively mount the sight either behind and to the side of the bow handle or to the front and side of the bow thus giving the hunter the option of determining which position of the bow sight is more suitable for reticle clarity. Under either option, the sight does not frame the arrow and the target together.
Calibration of the various individual sight devices is an important factor in the accuracy of the sight device and particularly so when the archer is hunting game. Although sophisticated bow sight aids allow accurate estimate of range such devices are mechanical in use and inhibit instinctive range finding by the hunter.